Tissue spectroscopy involves determining one or more characteristics of tissue inside a body by subjecting the tissue to light and detecting spectroscopic properties of the illuminated tissue. Tissue spectroscopy techniques are undergoing rapid development. For example, numerous light sources and detectors for use in tissue spectroscopy are being tested clinically. Current tissue spectroscopy systems tend to be large, bulky and expensive as they require external power supplies, light sources and spectrometer detection equipment.
In a typical tissue spectroscopy system, the excitation light from an external light source is delivered in vivo through an optical fiber to illuminate internal tissue. The optical fiber is placed inside a probe capable of being inserted inside a body cavity. The light emitted by the illuminated tissue, which indicates tissue characteristics, is delivered to an external detector through an optical fiber also placed inside the probe. The external devices tend to be bulky because-researchers are still exploring the use of various light excitation wavelengths, detection wavelengths and associated algorithms that may be found useful for detecting certain types of diseases. These diseases include cancer, displasia, various types of infections, viruses, inflammations, connective tissue disorders and autoimmune diseases.
Development of tissue spectroscopy devices tends to be slow, because research and validation work must be performed ahead of product design, which must then be approved by the various regulatory agencies, such as the U.S. Food and Drug Administration (FDA) and their foreign equivalents. To expedite the application of tissue spectroscopy, there remains a need for simple tissue spectroscopy devices that can be used in clinical settings. An example of such a device would be a portable tissue spectroscopy device which integrates all the features needed to successfully perform tissue spectroscopy in a simple housing insertable inside a body cavity. A portable tissue spectroscopy device which is simple to use and which displays the tissue spectroscopy result in an easily readible manner can also be used by patients as a self-test device.
For portable tissue spectroscopy devices to be successful, the devices need to be manufactured inexpensively and operate safely. The devices should be manufacturable with a small number of parts using existing manufacturing technologies. In addition, portable tissue spectroscopy devices should be able to protect the patients and the device operators from electrical shock and overexposure to light, which might occur with high power research units. The portable tissue spectroscopy devices should also permit reconfiguration for multiple uses over a variety of wavelengths of light, which may require the use of light wavelength ranges not typically used today, such that large amounts of hardware and expensive display equipment does not become obsolete in the future.